M4 x 20mm Socket Head Cap Screws Bolts 12.9 Grade Alloy Steel Metric Machine Hex Socket Screw, Black Oxide Finish, Fully Threaded, 50PCS

The material is made of high quality 12.9 grade alloy steel. Their surfaces are treated with black oxide, which has excellent corrosion resistance, firmness, wear resistance and low temperature resistance. Widely used in various precision machinery industries, classified instruments, meters, electronic products, household appliances, communication products, automobiles, locks, lamps, toys and so on. Specification: Thread Diameter 4 mm Head Diameter 7 mm Head Height 4 mm Screw Length 20 mm Allen Hex Drive 3 mm High Quality Material 12.9 Grade Alloy Steel Package Included: 50 PCS Socket Head Cap Bolts/Screws (M4 x 20mm) Warranty: Whenever you need us, please contact us by email or Q&A. We will provide you with professional services and reply to you as soon as possible. If you are not satisfied with the product, you can get a full refund, and you can buy it with confidence.